Handling "unbalanced" ship items

Hello,
ships fully loaded with torpedoes only, two tesla shields, two duct tapes, only mines etc. cause some trouble with balancing. Here is my idea:

Items decrease in effectiveness (lesser damage, lesser duration, lesser effect) when multiple items of the same type are loaded. E.g. "types" are torpedo, mortar, cannon, tesla shield, duct tape etc.
You may adjust the magnitude of the effect to the different types (e.g. two torpedoes should not degrade the effectiveness as much as two tesla shields) and three or more of a kind should decrease quite more than two.
This would also allow to increase perks and buffs for certain items again (e.g. tesla shield, tesla bolt, duct tape) which would be a positive effect for all ships using only one of them.

 

This idea has been pushed and shot down many times by players. Guild quests are the root cause of the issue, and I don't think reducing their effectiveness will force people to behave any differently... they are questing for a specific item with 10x contribution... reducing by 10% is still leaves the duplicate weapon 9x better than using a more unique weapon.